[PATCH] libata: return AC_ERR_* from issue functions

Return AC_ERR_* mask from issue fuctions instead of 0/-1.  This
enables things like failing a qc with AC_ERR_HSM when the device
doesn't set DRDY when the qc is about to be issued.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 8ff3a7f..b1ea2f9 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -427,7 +427,7 @@
 	void (*bmdma_start) (struct ata_queued_cmd *qc);
 
 	void (*qc_prep) (struct ata_queued_cmd *qc);
-	int (*qc_issue) (struct ata_queued_cmd *qc);
+	unsigned int (*qc_issue) (struct ata_queued_cmd *qc);
 
 	void (*eng_timeout) (struct ata_port *ap);
 
@@ -515,7 +515,7 @@
 extern void ata_host_stop (struct ata_host_set *host_set);
 extern irqreturn_t ata_interrupt (int irq, void *dev_instance, struct pt_regs *regs);
 extern void ata_qc_prep(struct ata_queued_cmd *qc);
-extern int ata_qc_issue_prot(struct ata_queued_cmd *qc);
+extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
 extern void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf,
 		unsigned int buflen);
 extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,